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A phoenix dying in Samos ashes: The SPARTAN reconnaissance satellite program
by Dwayne Day
Monday, January 24, 2022
One of the first American efforts to develop a reconnaissance satellite was known as Samos. Several of the Samos projects involved taking photographs using film and returning it to Earth in a reentry vehicle. One of these projects, designated E-6, was a search satellite equipped with two Eastman-Kodak cameras designed to photograph large amounts of territory at medium resolution. The satellite held promise but failed because of reentry vehicle problems. In 1963 the E-6 project was briefly revived as part of a program designated SPARTAN, the proverbial effort to make a silk’s purse out of a sow’s ear.
The early years
The United States’ first effort to develop a reconnaissance satellite was named Weapons System 117L. It began in 1956 and, around the time of Sputnik, split into several projects, including the Sentry reconnaissance program. Sentry was soon renamed Samos—which, contrary to some claims, was not an acronym for “satellite and missile observation system”—and Samos itself soon evolved into multiple programs. The Samos program was run by the Secretary of the Air Force Special Projects office, usually referred to either as SAFSP or, more commonly, “special projects.” Located in Los Angeles, SAFSP was part of the relatively new National Reconnaissance Office, a loose conglomeration of government agencies cooperating—more or less—on developing satellite reconnaissance systems. SAFSP cooperated with the Central Intelligence Agency on an offshoot program known as CORONA that returned its film to Earth in kettle-shaped reentry vehicles, achieving first success in August 1960.
One of the persistent misconceptions about Samos is that it was a film-readout system intended to develop film in orbit, scan it, and beam the images back to a ground station. The early Samos projects, known as E-1 and E-2, involved this technology. But Samos soon evolved to include the E-4 mapping system, the E-5 higher-resolution system, and the E-6 search system, all of which were designed to return their film to Earth inside reentry vehicles. Although E-4 was canceled before it ever took flight (E-3 never left the study phase), the Air Force launched both Samos E-5 and E-6 satellites starting in the early 1960s. But their reentry vehicles suffered problems and in early 1962 the E-5 program was canceled.
The Samos E-6 incorporated two 36-inch (0.91-meter) focal length Eastman-Kodak manufactured cameras that could scan large areas of the ground below at an estimated resolution of about six and a half feet (1.98 meters), good enough to spot and identify aircraft, ships, submarines, and possibly even military ground vehicles, and better than the early CORONA versions. (CORONA had a 24-inch/0.60-meter focal length.) After the film was exposed in the cameras it was wound up on spools inside the reentry vehicle.
by Dwayne Day
Monday, January 24, 2022
One of the first American efforts to develop a reconnaissance satellite was known as Samos. Several of the Samos projects involved taking photographs using film and returning it to Earth in a reentry vehicle. One of these projects, designated E-6, was a search satellite equipped with two Eastman-Kodak cameras designed to photograph large amounts of territory at medium resolution. The satellite held promise but failed because of reentry vehicle problems. In 1963 the E-6 project was briefly revived as part of a program designated SPARTAN, the proverbial effort to make a silk’s purse out of a sow’s ear.
The early years
The United States’ first effort to develop a reconnaissance satellite was named Weapons System 117L. It began in 1956 and, around the time of Sputnik, split into several projects, including the Sentry reconnaissance program. Sentry was soon renamed Samos—which, contrary to some claims, was not an acronym for “satellite and missile observation system”—and Samos itself soon evolved into multiple programs. The Samos program was run by the Secretary of the Air Force Special Projects office, usually referred to either as SAFSP or, more commonly, “special projects.” Located in Los Angeles, SAFSP was part of the relatively new National Reconnaissance Office, a loose conglomeration of government agencies cooperating—more or less—on developing satellite reconnaissance systems. SAFSP cooperated with the Central Intelligence Agency on an offshoot program known as CORONA that returned its film to Earth in kettle-shaped reentry vehicles, achieving first success in August 1960.
One of the persistent misconceptions about Samos is that it was a film-readout system intended to develop film in orbit, scan it, and beam the images back to a ground station. The early Samos projects, known as E-1 and E-2, involved this technology. But Samos soon evolved to include the E-4 mapping system, the E-5 higher-resolution system, and the E-6 search system, all of which were designed to return their film to Earth inside reentry vehicles. Although E-4 was canceled before it ever took flight (E-3 never left the study phase), the Air Force launched both Samos E-5 and E-6 satellites starting in the early 1960s. But their reentry vehicles suffered problems and in early 1962 the E-5 program was canceled.
The Samos E-6 incorporated two 36-inch (0.91-meter) focal length Eastman-Kodak manufactured cameras that could scan large areas of the ground below at an estimated resolution of about six and a half feet (1.98 meters), good enough to spot and identify aircraft, ships, submarines, and possibly even military ground vehicles, and better than the early CORONA versions. (CORONA had a 24-inch/0.60-meter focal length.) After the film was exposed in the cameras it was wound up on spools inside the reentry vehicle.
